Polyester is a class of polymers which contain the ester functional group in their main chain. Most commonly known polyesters are polyalkylene terephthalates include polyethylene terephthalate (PET), polytrimethylene terephthalate (PTT) and polybutylene terephthalate (PBT). Polyester fibers are known for properties such as high tenacity, low water absorption, resistant to mildew resistant, wrinkle resistant, and minimal shrinkage in comparison with other synthetic fibers. Major applications of polyester fibers include apparel, home furnishings such as carpets, curtains, draperies, wall coverings, and upholstery. Other applications of polyester fibers include hoses, conveyor belts, tire cords, and fiberfill as cushioning and insulating material in pillows, comforters and upholstery padding.
Applications of polyesters in industrial fabric, sportswear, rope, or carpet are constantly seeking methods to improve the wear or abrasion resistance of the polyesters. Methods to improve wear or abrasion resistance of polyester fiber include, for example, increasing the basic thickness of a fiber, altering the cross section shape of a fiber, or altering conditions during the spinning/drawing processes of the fiber. Alternatively, adding inorganic fillers with the polyester before melt spinning, is disclosed in JP4228113 wherein a woven fabric is made from PET yarns comprising 2% TiO2 exhibiting a high tear strength.
However, there is also a need to provide methods to further improve wear or abrasion resistance of polyester-based fibrous substrates (such as fabrics, yarns, carpets) by simple surface treatment with suitable coating or spraying compositions.
Coating or spraying compositions comprising fluoropolymer onto a fibrous substrate to change the physical/chemical properties are taught. For example, US2003/0139521 (U.S. Pat. No. 6,737,498) discloses a fluorochemical composition for rendering a fibrous substrate oil and/or water repellent. U.S. Pat. No. 4,929,471 discloses the use of polymers based on vinyl ethers that have a perfluoroalkyl group for treating polyester fabric during its manufacturing process so as to produce a polyester fabric that has similar physical properties as found in silk or rayon.
It is thus desirable to find a suitable surface treatment composition for polyester-based fibrous substrates to improve the wear or abrasion resistance.